one of my neighbor has the nastiest and the fattest cat named Nola.
She is a fighter. She scratches my housemate's dog (a shar pei) and always manage to win the fight.
Since she is the queen of the neighborhood, sometimes she can be found sleeping in my backyard

.
My veiled hate her so much. She doesn't care; but, Paul always jump off the tree and turn extreme black.
That is why I always have to guard the backyard when Paul and my other chams sunning outside.
I am more of a dog person.
But, cats are the only animal that kill for fun.
They will play with their victim for hours and hours.
So, moral of the story, keep them away from your chameleon.
The cat might decided to "play" with your chameleon.
Even when the cat doesn't care, the cham might be stressed out.